It is only needed for the higher boost pressures seen with a turbo upgrade, where the stock BPV is likely to leak/bleed. Aftermarket BPV/BOV cause problems. Don't ever use them on our TMIC setup.Jeff04FXT said:I was wondering what advantages changing stock bypass valve to STi or aftermarket one? Is it something you need to consider if you upgrade your Turbo? Thanks Jeff
ZuMBLe said:You can run the STi TMIC with the STi BPV with the stock turbo. I did it for a long time and it was fine.